GregorianCalendar.AddMonths(DateTime, Int32) 方法
定义
重要
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public:
override DateTime AddMonths(DateTime time, int months);public override DateTime AddMonths (DateTime time, int months);override this.AddMonths : DateTime * int -> DateTimePublic Overrides Function AddMonths (time As DateTime, months As Integer) As DateTime参数
- months
- Int32
要添加的月数。
返回
将指定月数添加到指定的 DateTime 中时得到的 DateTime。
例外
生成的 DateTime 超出了支持的范围。
示例
下面的代码示例根据公历显示 的 DateTime 多个组件的值。
using namespace System;
using namespace System::Globalization;
void DisplayValues( Calendar^ myCal, DateTime myDT )
{
Console::WriteLine( " Era: {0}", myCal->GetEra( myDT ) );
Console::WriteLine( " Year: {0}", myCal->GetYear( myDT ) );
Console::WriteLine( " Month: {0}", myCal->GetMonth( myDT ) );
Console::WriteLine( " DayOfYear: {0}", myCal->GetDayOfYear( myDT ) );
Console::WriteLine( " DayOfMonth: {0}", myCal->GetDayOfMonth( myDT ) );
Console::WriteLine( " DayOfWeek: {0}", myCal->GetDayOfWeek( myDT ) );
Console::WriteLine();
}
int main()
{
// Sets a DateTime to April 3, 2002 of the Gregorian calendar.
DateTime myDT = DateTime(2002,4,3,gcnew GregorianCalendar);
// Creates an instance of the GregorianCalendar.
GregorianCalendar^ myCal = gcnew GregorianCalendar;
// Displays the values of the DateTime.
Console::WriteLine( "April 3, 2002 of the Gregorian calendar:" );
DisplayValues( myCal, myDT );
// Adds two years and ten months.
myDT = myCal->AddYears( myDT, 2 );
myDT = myCal->AddMonths( myDT, 10 );
// Displays the values of the DateTime.
Console::WriteLine( "After adding two years and ten months:" );
DisplayValues( myCal, myDT );
}
/*
This code produces the following output.
April 3, 2002 of the Gregorian calendar:
Era: 1
Year: 2002
Month: 4
DayOfYear: 93
DayOfMonth: 3
DayOfWeek: Wednesday
After adding two years and ten months:
Era: 1
Year: 2005
Month: 2
DayOfYear: 34
DayOfMonth: 3
DayOfWeek: Thursday
*/
using System;
using System.Globalization;
public class SamplesGregorianCalendar {
public static void Main() {
// Sets a DateTime to April 3, 2002 of the Gregorian calendar.
DateTime myDT = new DateTime( 2002, 4, 3, new GregorianCalendar() );
// Creates an instance of the GregorianCalendar.
GregorianCalendar myCal = new GregorianCalendar();
// Displays the values of the DateTime.
Console.WriteLine( "April 3, 2002 of the Gregorian calendar:" );
DisplayValues( myCal, myDT );
// Adds two years and ten months.
myDT = myCal.AddYears( myDT, 2 );
myDT = myCal.AddMonths( myDT, 10 );
// Displays the values of the DateTime.
Console.WriteLine( "After adding two years and ten months:" );
DisplayValues( myCal, myDT );
}
public static void DisplayValues( Calendar myCal, DateTime myDT ) {
Console.WriteLine( " Era: {0}", myCal.GetEra( myDT ) );
Console.WriteLine( " Year: {0}", myCal.GetYear( myDT ) );
Console.WriteLine( " Month: {0}", myCal.GetMonth( myDT ) );
Console.WriteLine( " DayOfYear: {0}", myCal.GetDayOfYear( myDT ) );
Console.WriteLine( " DayOfMonth: {0}", myCal.GetDayOfMonth( myDT ) );
Console.WriteLine( " DayOfWeek: {0}", myCal.GetDayOfWeek( myDT ) );
Console.WriteLine();
}
}
/*
This code produces the following output.
April 3, 2002 of the Gregorian calendar:
Era: 1
Year: 2002
Month: 4
DayOfYear: 93
DayOfMonth: 3
DayOfWeek: Wednesday
After adding two years and ten months:
Era: 1
Year: 2005
Month: 2
DayOfYear: 34
DayOfMonth: 3
DayOfWeek: Thursday
*/
Imports System.Globalization
Public Class SamplesGregorianCalendar
Public Shared Sub Main()
' Sets a DateTime to April 3, 2002 of the Gregorian calendar.
Dim myDT As New DateTime(2002, 4, 3, New GregorianCalendar())
' Creates an instance of the GregorianCalendar.
Dim myCal As New GregorianCalendar()
' Displays the values of the DateTime.
Console.WriteLine("April 3, 2002 of the Gregorian calendar:")
DisplayValues(myCal, myDT)
' Adds two years and ten months.
myDT = myCal.AddYears(myDT, 2)
myDT = myCal.AddMonths(myDT, 10)
' Displays the values of the DateTime.
Console.WriteLine("After adding two years and ten months:")
DisplayValues(myCal, myDT)
End Sub
Public Shared Sub DisplayValues(myCal As Calendar, myDT As DateTime)
Console.WriteLine(" Era: {0}", myCal.GetEra(myDT))
Console.WriteLine(" Year: {0}", myCal.GetYear(myDT))
Console.WriteLine(" Month: {0}", myCal.GetMonth(myDT))
Console.WriteLine(" DayOfYear: {0}", myCal.GetDayOfYear(myDT))
Console.WriteLine(" DayOfMonth: {0}", myCal.GetDayOfMonth(myDT))
Console.WriteLine(" DayOfWeek: {0}", myCal.GetDayOfWeek(myDT))
Console.WriteLine()
End Sub
End Class
'This code produces the following output.
'
'April 3, 2002 of the Gregorian calendar:
' Era: 1
' Year: 2002
' Month: 4
' DayOfYear: 93
' DayOfMonth: 3
' DayOfWeek: Wednesday
'
'After adding two years and ten months:
' Era: 1
' Year: 2005
' Month: 2
' DayOfYear: 34
' DayOfMonth: 3
' DayOfWeek: Thursday
注解
如果生成的日期不是结果 DateTime 年份的月中的有效日期，则结果的日期部分将受到影响。 它更改为结果年份的结果月份中的最后一个有效日期。 如果生成的月份在指定 DateTime的年份之外，则结果DateTime的年份部分将受到影响。 此实现仅支持当前纪元。 因此， ArgumentException 如果生成的年份在指定 DateTime的纪元之外，则会引发 。 生成的 DateTime 的一天中的时间部分与指定的 DateTime保持相同。
例如，如果指定的月份是 10 月，它有 31 天，指定的日期是该月的第 31 天，参数的 months 值为 6，则生成的年份比指定的年份多一，生成的月份为 4 月，生成的日期为第 30 天，即 4 月的最后一天。
如果 参数的 months 值为负值，则生成的 DateTime 早于指定的 DateTime。
Kind返回DateTime值的 属性始终等于 DateTimeKind.Unspecified。 可以通过调用 DateTime.SpecifyKind 方法保留 Kind 参数的 time 属性，如以下示例所示。
returnTime = DateTime.SpecifyKind(cal.AddMonths(time, months), time.Kind);
returnTime = DateTime.SpecifyKind(cal.AddMonths(time, months), time.Kind)
